Matrix-addressed display systems such as, for example, liquid crystal displays, electroluminescent displays, and plasma displays, include a matrix display screen on which an array of pixels is defined by overlapping electrodes or other electrical or electronic components. A display image is typically formed by activating selected pixels, thereby generating light at the selected pixels or allowing light to pass through them.
Many display panel assemblies include two or three matrix display panels that are stacked together so that display images with multiple colors can be formed. Each matrix display panel defines pixel components that control or generate light of a selected color or group of colors. Pixel components from the different matrix display panels multiply by series transmission to form each of the colored pixels in the array.
In a liquid crystal display, for example, the pixel components are formed by a liquid crystal layer positioned between a pair of glass plates. The liquid crystal layer is typically much thinner than the glass plates. The glass plates of the separate display panels establish distances between the pixel components. These distances are typically greater than the lateral dimensions of the pixel components.
Such stacked matrix display panels can suffer relatively low light transmission capabilities. In particular, it can be difficult to maintain collimation of the light as it passes through successive pixel components. As a result, light rays passing through one pixel component tend to be misaligned with subsequent pixel components and, therefore, blocked by opaque regions of the subsequent display panels.
Another undesirable characteristic of many stacked matrix display panel assemblies is parallax. Parallax can occur because the thickness of the glass plates is so comparatively large that the alignment of the pixel components of a pixel can appear to change when the display screen is viewed from different angles. In a multicolor stacked arrangement, changes in the alignment of the pixel components can cause the color of a pixel to have an undesirable dependence on viewing angle. Moreover, the comparatively long optical paths between the stacked pixel components require a relatively large depth of field in, for example, projection display systems. Such a depth of field can be difficult to accommodate because it requires a light source with a small solid angular extent, as viewed from the liquid crystal display.